The search for the perfect APRS TNC…

[BMDaug]

So I think my search is over! I’ve been looking for a single device that can take the nmea gps sentences from my Harris XG100M manpack and do APRS smartbeaconing while also storing the nmea sentences locally for charting later.

Turns out the Microsat PLXTracker is freaking perfect for this! It ticks all the boxes for my project including: APRS with smartbeaconing, internal storage providing an entire day’s worth of tracking with five second tracking resolution (no thumb drive required), nmea input, additional serial input for optional telemetry, easy usb connectivity with user friendly configuration program, small, light, and inexpensive (under $60 including shipping).

Has anyone else used Microsat products, particularly the PLXTracker? They seem to be very high value while also being high quality with a solid feature set. It’s also a great time to support Polish businesses. They are doing a lot for the Ukrainian relief effort!

-B

 

[RFI-EMI-GUY]

So I think my search is over! I’ve been looking for a single device that can take the nmea gps sentences from my Harris XG100M manpack and do APRS smartbeaconing while also storing the nmea sentences locally for charting later.

Turns out the Microsat PLXTracker is freaking perfect for this! It ticks all the boxes for my project including: APRS with smartbeaconing, internal storage providing an entire day’s worth of tracking with five second tracking resolution (no thumb drive required), nmea input, additional serial input for optional telemetry, easy usb connectivity with user friendly configuration program, small, light, and inexpensive (under $60 including shipping).

Has anyone else used Microsat products, particularly the PLXTracker? They seem to be very high value while also being high quality with a solid feature set. It’s also a great time to support Polish businesses. They are doing a lot for the Ukrainian relief effort!

-B

Looks interesting. I did see that it is coming from Poland. Hopefully the supply chain is good.

 

[AK9R]

internal storage providing an entire day’s worth of tracking with five second tracking resolution

Since the PLXtracker has no internal time-of-day clock, I imagine that these saved track points are not timestamped.

Also, the PLXtracker doesn't seem to have a KISS interface. That might be a limitation when interfacing the device with an APRS client program running on a computer. Based on my quick read of the manual, there doesn't seem to be any provision for using the device as a modem with an APRS client program.

As a matter of personal preference, I'd rather than RS-232 connector be a DB-9 rather than a mini-DIN.

Did you consider the Byonics TinyTrak4? Though, it does not have the track point memory.

 

[BMDaug]

@AK9R Thanks for the feedback! So the nmea sentences include time and date, which I suppose could be used for file naming… the manual mentions storing time and date and being able to extract the sentences over usb for use with internet mapping sites.

They do make a model with Bluetooth and serial kiss support (and several other modem types), but that one doesn’t have local storage. I chose this model so that I could get away from the computer and the phone so I won’t miss those features, but it’s definitely worth mentioning that shortcoming.

I did consider that Byonics, but my two main requirements are APRS sending with smartbeaconing and local storage tracking in a single unit. That’s why I didn’t consider other options from Microsat! I do wish the serial interface was a locking connector but at $45 it wasn’t a deal breaker! Since I’m running this in a manpack, the number of devices and associated wiring needs to be minimal so I didn’t want to go with a more full-featured modem and then need a separate tracker (which often also requires a flash drive)… I may add a telemetry option later to capture voltage, temperature, etc. as well… it just never ends!

-B

 

[AK9R]

Yes, if it's saving NMEA sentences, then you'll have date and time. You may have to jump through some hoops to convert NMEA sentences to something that a mapping site can use. Looks like Google Earth Pro can read NMEA sentences from a file, though I've never tried it.

The Byonics TinyTrak4 can be configured for SmartBeaconing, though it doesn't have the local storage you are looking for.

A tip about mini-DINs. Unless you enjoy doing really fine work with a soldering iron, find cables with the appropriate mini-DIN connectors pre-installed. I use mini-DIN connectors with Kenwood radios. In the past, I've been able to find cables with male mini-DINs on both ends. I just cut the cable in half, attach DB-9 connectors to the cut ends, and I have two useful cables. I think the Microsat device uses 6-pin mini-DINs, so pay attention to the pin count when ordering connectors or cables.

 

[BMDaug]

Yes, if it's saving NMEA sentences, then you'll have date and time. You may have to jump through some hoops to convert NMEA sentences to something that a mapping site can use. Looks like Google Earth Pro can read NMEA sentences from a file, though I've never tried it.

The Byonics TinyTrak4 can be configured for SmartBeaconing, though it doesn't have the local storage you are looking for.

A tip about mini-DINs. Unless you enjoy doing really fine work with a soldering iron, find cables with the appropriate mini-DIN connectors pre-installed. I use mini-DIN connectors with Kenwood radios. In the past, I've been able to find cables with male mini-DINs on both ends. I just cut the cable in half, attach DB-9 connectors to the cut ends, and I have two useful cables. I think the Microsat device uses 6-pin mini-DINs, so pay attention to the pin count when ordering connectors or cables.

Great minds think alike! That’s just what I did! The other end of the connector is going to be a 40 pin Dsub connected directly to the Harris XG-100M accessory port so I’m gonna have to solder one end or the other!

-B

 

[AK9R]

Somewhere along the way, I obtained a crimper for DB connector pins. Now, I buy only connector shells that can accept pins along with loose pins. I crimp the pins onto the wires and then insert them into the shells. Easier for me than soldering to shells with solder cup pins.

 

[BMDaug]

That’s cool! For db25 and db9 as well as other low density dsubs, I do have a crimper, but the pins on this 44 pin dsub are super small. I’m not sure my crimper would work and I didn’t feel like buying parts twice f it didn’t. Good thing it’s just a few wires because soldering 44 connections at that density would be terrible! you’re spot on with the crimper!!

For radio connections like ptt and audio, I frequently use dsub to screw terminal connectors so the parts are field serviceable. I also found a dsub panel punch at some point so I can panel mount connectors when needed… that was the most expensive punch I’ve ever bought…

-B